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arXiv · 1004.2091

An O(M(n) log n) algorithm for the Jacobi symbol

Richard P. Brent·Paul Zimmermann
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Abstract

The best known algorithm to compute the Jacobi symbol of two n-bit integers runs in time O(M(n) log n), using Schönhage's fast continued fraction algorithm combined with an identity due to Gauss. We give a different O(M(n) log n) algorithm based on the binary recursive gcd algorithm of Stehlé and Zimmermann. Our implementation - which to our knowledge is the first to run in time O(M(n) log n) - is faster than GMP's quadratic implementation for inputs larger than about 10000 decimal digits.

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Richard P. Brent, Paul Zimmermann. 2010-06-02. An O(M(n) log n) algorithm for the Jacobi symbol. https://arxiv.org/abs/1004.2091

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